The main characteristics of the general atmospheric circulation in January 2024 are as follows. There were two polar vortex centers in the Northern Hemisphere. The Eurasian mid- and high-latitude circulation showed a two-trough-one-ridge pattern. The East Asian trough was more eastward. The monthly mean precipitation (16.3 mm) over China was 15.6% more than normal (14.1 mm). The monthly average temperature was -3.8℃, which was 1.0℃ higher than that in the same period of normal years. Cold and warm temperatures fluctuated greatly during the month. There was one nationwide cold wave process and two widespread persistent fog-haze weather processes, among which the cold wave weather process from 20 to 22 January presented the characteristics of a wide range of influence, and cooling, long duration of strong wind and heavy snowstorm.